SummaryThe paper reports the length-weight relationships of 55 species from the Three Gorges Reservoir (TGR) of the Yangtze River, China, and the largest reservoir in the world. A total of 24,176 specimens were collected from July 2012 to January 2015.Length-weight relationships for 33 fish species not recorded previously in FishBase, and the maximum total lengths computed for eight species are presented. The a values varied between 0.00054 and 0.01923, and the b values ranged from 2.729 to 3.583.The results will be useful for the application of sustainable management and conservation of these fishes in the TGR of the Yangtze River.